Mark,
yes the block has been bored, I have no idea what the sonic check looked like, lets hope the cylinder castings were straight & true!
600 bhp at the rear wheels is only a dream at this point. He has the boost turned down until he fits inter-coolers, after inter-coolers are on he'll crank it to 14 psi (1 atmosphere). As you probably know, that doubles the bhp the engine would make naturally aspirated. The motor has a lightweight fordged crank. Shifts at 7300 rpm. He had 125 bhp nitrous on the motor prior to the turbos, & plans to reinstall the nitrous as a secondary power adder! Jeez!
Anyway, he's pulling 11.5 second quarter times in a '73 Mach One 'Stang at the moment, 4 speed, 3.89 gears.
I suppose I would be wasting my time asking him if 500 bhp were enough! lol........ I never have understood drag racers, although many of my friends have been 1/4 mile nuts.
your friend on the DTBB, George